Using transgenic T cells specific to different H-Y antigens, Perez-Diez and colleagues were able to demonstrate in 6 different tumor models that CD4+ T cells were more effective than CD8+ T cells (or a mixed population of both CD4+ and CD8+ T cells) at rejecting tumors even in the absence of MHC-II expression on the tumor cells [98]. The gene discussed is CD8A; the disease is neoplasm.